<h2>
Answer:</h2>
The statement that is true about the radius of a sphere is:
The radius is a line segment from the center point to the surface of the sphere.
<h2>
Step-by-step explanation:</h2>
We know that the radius of a circle/sphere is a line segment that joins the center of circle/sphere to any point on the circumference/ surface of the circle/sphere.
Also, in a circle the radius is the length such that each point on the circumference are equidistant from the center of the circle.
Answer:
-2 < x
Step-by-step explanation:
-6x - 16 < 2x
Add 6x to each side
-6x+6x - 16 < 2x+6x
-16 <8x
Divide by 8
-16/8 < 8x/8
-2 < x
Answer:
b. CHISQ.TEST
Step-by-step explanation:
Notation and previous concepts
A chi-square test is "used to test if the variance of a population is equal to a specified value. This test can be either a two-sided test or a one-sided test. The two-sided version tests against the alternative that the true variance is either less than or greater than the specified value"
The statistic is given by:

In order to calculate the p value we need to have in count the degrees of freedom , on this case
. And we can calculate the p value would be given by:
But the correct comand is given by:
b. CHISQ.TEST(Actual range, Expected range)
We just need to put in one column the Observed values and in other the expectec values.
I think the answer is Sample 4.
Hope this helps!
Answer:
The test statistic is 
Step-by-step explanation:
We are interested in determining whether or not the proportion of the student who experience anxiety during the exam is significantly more than 80%.
At the null hypothesis, we test if the proportion is 80%, that is:

At the alternate hypothesis, we test if the proportion is more than 80%, that is:

The test statistic is:

In which X is the sample mean,
is the value tested at the null hypothesis,
is the standard deviation and n is the size of the sample.
80% is tested at the null hypothesis:
This means that 
A random sample of 100 students was taken. Eighty-five of the student in the sample experienced anxiety during the exam.
This means that 
The test statistic is



The test statistic is 